Immediate

Activity Predecessor$($s$)$ Pessimistic Probable Optimistic

$\backslash$table$[[$J$,--,15,10,8],[K,--,9,8,7],[L,J,10,6,5],[M,J,3,3,3],[$N$,$K$,$M$,9,5,1],[O,K,M,10,7,4],[P,L,N,10,8,3]]$

a$.$ Calculate the expected duration of each activity.

b$.$ Calculate the expected duration and variance of the critical path.

c$.$ Calculate the probability that the project will be completed in fewer than $30$ time units.